This invention relates to an actuatable film type display device, and more particularly to an actuatable film type display device which can be driven without a refresh process and can be easily manufactured.
The entire contents of Japanese Patent Application No. 8-259520 filed on Sep. 30, 1996 are incorporated herein by reference.
Recently, it is required to reduce the weight and lower the power consumption of large-sized display devices and small-sized display devices which can be applied to portable equipments.
Conventionally, a display device disclosed in Jpn. Pat. Appln. KOKAI Publication No. 60-131174 is provided.
FIG. 1 shows a cross section of one pixel of a display device disclosed in the above Publication. Fixed electrodes 1, 2 are formed to have mirror-like surfaces, one side surface of a foil (actuatable portion) 3 is painted in white and the other side surface thereof is painted in black. The color of the exposed portion of the foil 3 is reflected on the opposite mirror surface, and the color of the exposed portion of the foil 3 and the color reflected on the mirror surface are observed by an eye 4 of a man. Since the foil 3 has an electrically conductive property and the foil can be attracted to one of the fixed electrodes depending on the potential thereof, the colors of the front and back surfaces of the foil can be selectively displayed by electrically changing the position of the foil 3.
However, the above display system cannot be applied to a color display system for three or more colors in principle, and even in a case of two-color display, the angle of visibility is small since the mirror-like surfaces are used, and it is difficult to attain clear display.
A driving circuit of the above display device has a construction shown in FIG. 2. In FIG. 2, a foil S is used as a signal line and applied with a potential 0 or E, and a fixed electrode F1 which is one of the fixed electrodes is used as a scanning line and applied with a potential 0 or 2E. The potential of the other fixed electrode F2 is commonly used for all of the pixels and the potential thereof is set to E or 2E.
The flow of control of the potentials of the electrodes is shown in FIG. 3. As shown in FIG. 4, in the above display system, cycles of (A) initialization, (B) re-painting of pattern, and (C) display of still picture are repeatedly effected.
However, in the above display system, the display screen is always set to a preset refresh display screen in the initialization step and continuous pictures cannot be displayed. That is, it is necessary to effect the refresh process for the entire display screen before writing and it is necessary to momentarily display the same picture on the entire display screen at the refreshing time, and there occurs a problem that continuous moving pictures cannot be displayed.
Further, the above display device cannot display three or more colors for one pixel. Even if two-color display is used, the angle of visibility is small since the mirror-like surfaces are used, and it is impossible to attain clear display.